The true story of SV40, the cancer-causing virus hidden in polio vaccines

Poliomylitis, or polio for short, is a disease that has been around since ancient times, and despite the medical advances we have made in the United States in terms of regular and natural health, there is still no cure for this dreaded, disabling disease.

An infectious viral affliction that attacks nerve cells and, at times, the body’s central nervous system, polio causes a phenomenon known as muscle wasting (a decrease in the mass of muscle), and can also cause paralysis and death.

“Since 1900 there had been cycles of epidemics, each seeming to get stronger and more disastrous. The disease, whose early symptoms are like the flu, struck mostly children, although adults, including Franklin Roosevelt, caught it too,” said a report in the journal A Science Odyssey.

In 1952 that all changed, when Dr. Jonas Salk, a medical student and virus researcher, developed a vaccine against polio that, two years later, was accepted for testing nationwide. The principle behind the vaccine was simple and familiar: Like the vaccine that had been developed to fight smallpox, the polio vaccine introduced a small amount of the virus into the body, which then developed antibodies and an ability to fight off more powerful strains of the disease.

Admittedly, Salk’s vaccine logged early success; some 60-70 percent of those vaccinated did not develop the disease. But it also saw some early problems. About 200 people who had been vaccinated got the disease, and 11 of them died, forcing a halt to all testing. Once it was determined that a faulty, poorly manufactured batch of the vaccine was the cause of those cases, stricter production standards were implemented and full-scale vaccinations nationwide resumed once more. Four million vaccines were given by 1955; by 1959, 90 countries were using it.

That said, those early cases were far from the last time the vaccine killed. In fact, throughout its history of use, Salk’s polio vaccine left a path of death its wake.

A deadly discovery

Production and nationwide distribution of the polio vaccine was in full force by the end of the 1950s, but between 1959 and 1960 Dr. Bernice Eddy, a researcher with the National Institute of Health (NIH), made a startling discovery.

While examining the minced kidney cells of rhesus monkeys – from which the the polio vaccines were derived – she discovered “that the cells would die without any apparent cause,” according to a report by Michael E. Horwin, M.A., J.D., published in the Nov. 3, 2003, issue of the Albany Law Journal of Science & Technology.

Horwin writes:

Dr. Eddy discovered that the cells would die without any apparent cause. She then took suspensions of the cellular material from these kidney cell cultures and injected them into hamsters. Cancers grew in the hamsters. Shortly thereafter, scientists at the pharmaceutical company Merck & Co. discovered what would later be determined to be the same virus identified by Eddy. This virus was named Simian Virus 40 or SV40 because it was the 40th simian virus found in monkey kidney cells.

A few months later, in 1960, Dr. Benjamin Sweet and Dr. Maurice Hillman, both Merck scientists, published their findings. They wrote that such viruses were common in that particular breed of money, particularly in their kidneys:

The discovery of this new virus, the vacuolating agent, represents the detection for the first time of a hitherto “non-detectable” simian virus of monkey renal cultures and raises the important question of the existence of other such viruses . . . . As shown in this report, all 3 types of Sabin’s live poliovirus vaccine, now fed to millions of persons of all ages, were contaminated with vacuolating virus…

The term “vacuolating virus” is another name for SV40, Horwin said, adding that later, in 1962, Dr. Eddy published more findings regarding the link between cancer and SV40:

The (SV40) virus was injected at once into 13 newborn hamsters and 10 newborn mice. Subcutaneous neoplasms indistinguishable from those induced by the rhesus monkey kidney extracts developed in 11 of the 13 hamsters between 156 and 380 days…

Chorus of Denial

Shortly after Dr. Eddy’s discovery was made public, a host of high-powered researchers and scientists, including Dr. Salk himself, stepped forward to defend the polio vaccine.

An Associated Press story published April 7, 1963 (“New Data Ties Cancer, Virus”), featured quotes from a number of scientists who all pointed out that, to date, no link between SV40 and cancer had been discovered in humans.

“It seems to me that if danger were attached to SV-40, we would recognize it by now,” the AP quoted Dr. Michael B. Shimkin of the National Cancer Institute as saying. Dr. Shimkin went on to say that “the public can be reassured” because careful studies “have produced no evidence whatsoever that during the last seven years there has been an increase in leukemia or cancer which can be attributed to SV-40.”

Dr. Joseph L. Melnick of Baylor University in Texas agreed, saying that there had been no link discovered, a claim echoed by Dr. Salk, according to the AP story. Even Dr. Eddy “said this virus is not known to induce tumors in man or monkeys,” the report said.

Mounting Evidence

By 1960, Horwin notes, the Salk injectable polio vaccine had been given to about 98 million American children and adults, while Sabin’s oral version had been given to about 10,000 Americans and tens of millions of Soviet citizens, where trials had been conducted. “It was estimated that 10% to 30% of the vaccines contained live SV40,” he wrote, noting that despite the link discovered by Dr. Eddy, no federal agency and no new federal rules that regulated the manufacture, sale and distribution of vaccines required makers of the polio vaccine to “discard their SV40-contaminated poliovirus seeds which were the source for all subsequent polio vaccines.”

Subsequent federal testing of the vaccines, which occurred in the mid-1960s, were also inadequate, Horwin notes, because “the fourteen-day SV40 tests were not long enough to detect the virus.” Yet in the years afterward, the incidence of pediatric cancer increased.

“Indeed, the pediatric cancer rate continued to climb through the 1960’s, 70’s, 80’s and 90’s,” he wrote.

That claim is backed by other research as well.

“Whether childhood cancer is becoming more common is a controversial question among scientists,” writes Amy D. Kyle, for EnviroHealthPolicy.net.

“Data from the cancer tracking systems in the US suggest that childhood cancer is increasing,” she adds, noting a graph which tracked the increase in pediatric cancer rates in the latter part of the 20th century.

In 2005 the National Network for Immunization Information published a somewhat conflicting report regarding a link between SV40 and increased cancer rates.

“Although SV40 has biological properties consistent with a cancer-causing virus, it has not been conclusively established whether it has caused cancer in humans,” said the report. “Epidemiological studies of groups of people who received polio vaccine during 1955-1963 do not show an increased cancer risk.”

But later, the same report seems to contradict itself:

However, a number of studies have found SV40 in certain forms of cancer in humans, such as mesotheliomas – rare tumors located in the lungs – brain and bone tumors; the virus has also been found to be associated with some types of non-Hodgkin’s lymphoma.

In 2002, the IOM’s (Institute of Medicine) Immunization Safety Review Committee considered that the available data was inadequate to conclude whether or not the contaminated polio vaccine may have caused cancer. Because there is biological evidence supporting the theory that SV40-contamination of polio vaccines could contribute to human cancers,the committee recommended continued public health attention in the form of policy analysis, communication, and targeted biological research.

A corresponding study by the National Academy of Sciences, conducted at the request of the Centers for Disease Control and Prevention, was similarly “inconclusive.” A panel of medical and scientific experts charged with examining any potential link between SV40 and increased cancer risk concluded:

Available evidence is “inadequate to accept or reject a causal relationship between SV40-containing polio vaccines and cancer;”

The “biological evidence is moderate that SV40 exposure could lead to cancer in humans under natural conditions;”

The “biological evidence is moderate that SV40 exposure from the polio vaccine is related to SV40 infection in humans.”

In the “Significance Assessment” portion of its conclusions, the panel’s final report said, “The committee concludes that concerns about exposure to SV40 through inadvertent contamination of polio vaccines are significant because of the seriousness of cancers as the possible adverse health outcomes and because of the continuing need to ensure and protect public trust in the nation’s immunization program.”

While the panel did not recommend “a policy review of polio vaccine by any of the national or federal vaccine advisory bodies” because the current polio vaccine is free of SV40, it did recommend “development of sensitive and specific serological tests” for the virus, as well as “development and use of … standardized techniques for SV40 detection.

Real Cases – Real Conclusions

In a July 15, 2001 report, the San Francisco Chronicle published a story detailing an increased concern among researchers that the SV40 virus found in those early polio vaccines was indeed responsible for higher cancer rates.

“For four decades, government officials have insisted that there is no evidence the simian virus called SV40 is harmful to humans. But in recent years, dozens of scientific studies have found the virus in a steadily increasing number of rare brain, bone and lung-related tumors – the same malignant cancer SV40 causes in lab animals,” the report said. “Even more troubling, the virus has been detected in tumors removed from people never inoculated with the contaminated vaccine, leading some to worry that those infected by the vaccine might be spreading SV40.”

Dr. Michele Carbone of Loyola University Medical Center in Maywood, Ill., told the paper he believed the virus was carcinogenic in humans.

“We need to be creating therapies for people who have these cancers, and now we may be able to because we have a target – SV40,” he said.

Others say the few government studies regarding the potential link have been flawed.

Barbara Loe Fisher, president and co-founder of the National Vaccine Information Center, a non-profit organization which advocates vaccine safety, testified before the House Government Reform Committee’s subcommittee on Human Rights and Wellness in September 2003 that

[T]oday, U.S. federal health agencies admit the following two facts: (1) Salk polio vaccine released for public use between 1955 and 1963 was contaminated with SV40; and SV40 has been proven to cause cancer in animals.

Continuing, Fisher said that at a 1997 conference on SV40 and human cancers held by the National Institutes of Health which she attended, “there was no disagreement among both government and non-government scientists about these two facts.

The only disagreement was whether SV40 was actually being identified in the cancerous tumors of children and adults alive today and, if it was, whether the monkey virus was in fact responsible for their cancer. Non-government scientists working in independent labs around the world said, ‘Yes.’ But the scientists connected with the U.S. government said ‘No.'”

Fisher went on to say that “credentialed non-government scientists in multiple labs around the world continue to identify SV40 in human brain and lung cancers of children and adults and are finding that SV40 is also associated with bone cancers and Non-Hodgkin’s Lymphomas.”

Despite ongoing denials, an increasing number of researchers continue to maintain that not only is there a bona fide link between Salk’s SV40-tainted vaccines and cancer, that federal government officials and agencies responsible for ensuring the safety of such vaccines – then and now – are loathe to admit it, perhaps because they fear the fallout in terms of lawsuits and lost credibility.

But eventually there is likely to be enough evidence to force a change of heart, because based on what’s still being discovered about the link, the issue won’t go away anytime soon.